The Nassau Hub Transit Initiative: Livable communities through sustainable transportation
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glossary of terms


Accessibility: The ability to use transit without physical, social or economic barriers. Improvements in access to public transportation link geographic areas that were previously poorly connected.

Alignment: The physical location, or right-of-way, for the horizontal and vertical placement of a transportation facility (e.g., road, railway, fixed guideway, etc.)

Alternative: Potential solutions to a transportation problem or series of problems that may consist of different configurations, alignments, types of access, or transportation modes and strategies.

Alternatives Analysis (AA): A process required by the Federal Transit Administration (FTA) to prioritize and select the most appropriate transit projects within a corridor or region.

Arterial Road: A major roadway used for through traffic that is characterized by high volume, travel speeds, and continuity of movement.

At-Grade Crossing: An intersection where the rail and roadway (or pathway) cross at the same level.

Automated Guideway Transit (AGT): (can also be called: personal rapid transit, group rapid transit, or people mover) Guided electric transit that operates without an onboard crew. Service may be in response to a passenger-activated call button or on a fixed schedule such as the JFK Airport AirTrain.

Average Daily Traffic (ADT): The average number of vehicles passing a fixed point in a 24-hour time frame, which is used for measuring traffic volume.

Average Trip Length: The average distance a passenger travels on a single mode, which is computed as total passenger miles divided by total number of passenger trips.

Average Passenger Load: The average number of passengers aboard a vehicle in revenue service.

Baseline Alternative: The best solution to improve transportation facilities and services in a corridor without major capital expenditures.

Bus: (also called motor bus) A mode of local or express transit characterized by roadway vehicles powered by diesel, gasoline, battery, or alternative fuel engines that operate on roadways along a fixed-route. Local buses stop frequently; those limited to short-distance trips are often called circulator, feeder, trolley, neighborhood, or shuttle service. Express buses make fewer stops and are also known as limited-stop service or bus rapid transit (BRT).

Bus Rapid Transit (BRT): BRT is a high-speed bus service that operates within an exclusive right-of-way thus combining certain service characteristics (e.g., adherence to schedule) of rail transit with the flexibility of buses (i.e., including the ability to exit the exclusive right-of-way to serve adjacent activity centers).

Transit Capacity: The maximum number of riders that a transit car, line, or system can carry, which is measured in riders per hour past a designated point in one direction.

Capital Costs: One-time costs required to construct or improve a transit system. Examples include purchasing locomotives and passenger cars; construction and rehabilitation of stations, tracks, and maintenance facilities; and associated design and administrative costs associated with these improvements.

Central Business District (CBD): The portion of a region designated for intense business activity, which is characterized by large numbers of pedestrians, commercial vehicle loadings of goods and people, high demand for parking space, and frequent parking turnover.

Catenary: The overhead wires of an electrification system which provides power to a trolley. This comprises a support cable hung between pylons on a railway track and an electrical wire suspended from the support cable to power the trolley.

Commuter Rail: (also called metropolitan rail, regional rail,or suburban rail) A mode of transit service using electric- or diesel-propelled power to provide regular urban passenger train service between a central city and adjacent suburbs. Service is generally characterized by multi-trip tickets, specific station-to-station fares, railroad employment practices and usually only one or two stations in the CBD. Intercity rail service is excluded, except for that portion of such service that is operated by or under contract with a public transit agency for predominantly commuter services. Most service is provided on routes of current or former freight railroads. Commuter rail providers in the New York region include Long Island Rail Road, Metro-North Railroad, and NJ TRANSIT.

Congestion: A condition that occurs when user demand on a transportation system (i.e., roadway or transit route) exceeds the capacity of the system during any period of the day, which often occurs during the peak commuter periods and before and after events that attract many users or participants.

Consist: The number of cars or coaches forming a train.

Corridor: A long, generally linear land area with an existing or planned transportation facility along the center line.

Cost Effectiveness Index (CEI): A measure used in FTA’s New Starts process to evaluate transit projects for funding.  The CEI is defined as the ratio of incremental cost to transportation system user benefits. Cost per new rider is an example of a CEI.

Double Track: Two sets of main line track located side by side most often used for travel in opposite directions, but can be used for same direction service.

Embedded Track: Rail embedded in the roadway to allow other traffic and pedestrians to move safely and smoothly across the track.

Environmental Impact Statement (EIS): A detailed analysis of the environmental impacts of a proposed project seeking federal funds and/or approvals and likely to result in significant environmental effects.  A federal EIS must follow guidelines of the National Environmental Policy Act (NEPA) and its implementing regulations. A Draft EIS (DEIS) is circulated to the public and agencies for comment. A Final EIS (FEIS) presents responses to public and agency comments, modifications to analyses and/or documentation presented in the DEIS, and commitments to mitigate adverse impacts.

Environmental Justice: A federal policy that provides equitable outreach benefits to minorities, low-income, and other historically underserved populations and requires that adverse environmental effects do not disproportionately affect them.

Exclusive Right-of-Way: A right-of-way used only for a rail line or bus service with grade-separation from other types of vehicles or integration of crossings with other vehicles.

Express Bus: A bus that operates on a portion of its route without stops or with a limited number of stops.

Federal Transit Administration (FTA): An agency of the U.S. Department of Transportation that administers federal grants to public transit to help plan, build, and operate rail, bus, and paratransit systems.

Feeder Bus: A bus service that picks up and delivers passengers to a rail station, express bus stop, or any other designated destination.

Fixed Guideway A fixed facility for the operation of transit vehicles with a vehicle guidance system such as rails or beams.

Frequency: A term used to describe how often transit service is provided at a station or along a route.

Geometrics: An engineering term that, for transit facilities, refers to the design of tracks.

Grade Crossing: The area along a track where a roadway or pathway crosses it.

Grade-Separated: The condition of vertical separation between two transportation facilities, such as a roadway crossing over a railroad track.

Heavy Rail: (also called: metro, subway, rapid transit, or rapid rail) A mode of transit service operating on an electric railway with capacity for heavy traffic volume. It is characterized by high speed and rapid acceleration passenger rail cars, separate designated rights-of-way, sophisticated signaling, and high platform loading. Examples include the New York City subway, San Francisco’s BART, and Washington, DC’s Metrorail.

Initial Operating Segment (IOS): A segment of the full transit service that will be built first to operate passenger service before the full transit alignment is built.

Kiss and Ride: A place where commuters are driven and dropped off at a station to board a public transportation vehicle. Kiss and Ride parking lots are common near suburban commuter rail and bus stations.

Layover Time: Time built into a schedule between the arrival of a transit vehicle at the end of its route and its departure for the return trip, used for recovering delays and preparing for the return trip.

Light Rail: (also called: streetcar, tramway, or trolley) A mode of transit service operating passenger rail cars singly (or in short, usually two- or three-car, trains) on fixed rails in right-of-way that is often separated from other traffic. Light rail vehicles are typically powered electrically from overhead wires via a trolley or a pantograph; driven by an operator on board the vehicle; and may be either high- or low-loading using platforms or steps. Examples include the Hudson Bergen Light Rail in New Jersey and Portland, Oregon’s MAX system.

Metropolitan Planning Organization (MPO): The entity designated by law with lead responsibility for developing transportation plans and programs for urbanized areas of a population larger than 50,000 individuals. MPOs are established by agreement of the Governor and units of general purpose local government, which together represent 75 percent of the affected population or an urbanized area. The New York Metropolitan Transportation Council (NYMTC) is the MPO for Nassau County, as well as Suffolk, Westchester, Rockland and Putnam Counties; New York City; and the MTA.

Mode: A system for carrying transit passengers, which is described by specific right-of-way, technology, and operational features.

Modern Streetcar: A form of light rail best suited to short trips in activity centers, usually operated in mixed traffic and making frequent stops.

Monorail: An electric railway of guided transit vehicles operating single- or multi-car trains, which are suspended or straddle a guideway formed by a single beam, rail, or tube.

Model: An analytical tool used by transportation planners to forecast future land use, economic activity, and travel activity, as well as their effects on the quality of resources such as land and capacity.

New Starts: Federal funding grants under Section 3(i) of the Federal Transit Act, which are made available to build or extend a fixed guideway system. Grants are based on cost-effectiveness, alternatives analysis results and the degree of local financial commitment. The proposed project must follow a strictly defined project development process in order to qualify for a grant.

National Environmental Policy Act (NEPA): An act passed by Congress to regulate negative effects that construction and transportation projects may impose on the environment. Federal legislation requires consideration of environmental consequences of a project before the project can begin. If a study indicates that there would be adverse environmental consequences from a proposed project, the project must incorporate “mitigating” measures to reduce environmental damage or provide an alternative that would be less damaging to the environment. NEPA applies to any major federal, state, county, city, or industrial project that requires a federal permit or receives funding from a federal agency.

OCS (Overhead Catenary System): The part of the overhead line equipment consisting of: contact wire, contact wire supports, messenger wires, isolators, counter-weights, hangers, and other equipment and assemblies that distributes DC electric power from substations to a light rail vehicle.

Operational Costs (Operating Costs): Recurring costs of operating passenger service, which include wages, maintenance of facilities and equipment, fuel, supplies, employee benefits, insurance, taxes, marketing, and other administrative costs.

Park and Ride Lot: Designated parking areas for automobile drivers who board transit vehicles, or form carpools at those locations.

Passenger Miles: The cumulative sum of the distances ridden by all passengers.

Public Transportation: (also called: transit, public transit, or mass transit) Transportation by a conveyance that provides regular and continuing general or special transportation to the public, excluding school buses, charter, and sightseeing services.

Purpose and Need Statement: A clear and well-documented statement of the purpose of and need for a proposed project, based on the transportation and related problems that have been identified in a corridor or study area.  The purpose and need, and related project goals and objectives, are the foundation for the development of a range of alternatives for consideration.

Record of Decision (ROD): Under the National Environmental Policy Act (NEPA), a public document that reflects the lead federal agency's final decision about a proposed action or project and concludes the EIS process. The ROD identifies the selected alternative, all alternatives considered and the basis for the decision; identifies the environmental preferable alternative; and states project commitments to monitor and mitigate environmental impacts.

Right-of-Way: The strip of land owned by or under direct control of a transportation system, which is occupied by or intended for a transportation line. Right-of-way is granted by deed or easement for construction and maintenance of the designated use, which may include highways, streets, railroads, canals, ditches or other public uses.

Rail Yard: A system of tracks within defined limits designed for storing, cleaning, and linking rail.

Ridership: The number of people carried by a transit system during a specified period of time.

Rolling Stock: The vehicles used in a transit system.

Route Miles: The total number of miles included in a fixed-route transit system network.

Scoping: The process by which public and agency input is obtained regarding the issues to addressed in an EIS, including the project purpose and need, the range of alternatives, issues and areas of concern to be evaluated, methodologies to be used, among others. Scoping is used to facilitate cooperation and early resolution of potential conflicts in EIS preparation and to improve the EIS as a decision-making tool.

Substation: A building or structure containing rectifiers, breakers, and other electrical equipment used to change local utility power into power able to be transmitted to the OCS and used by the vehicles.

Transit Center: A primary station in a multi-destination transit system where passengers may conveniently transfer among lines and local feeder routes.

Transportation System Management (TSM): TSM is a relatively low cost approach to help address transportation problems in a corridor.  Examples include upgrades in transit service through operational and small physical improvements, selected highway upgrades through intersection improvements, minor widenings, and other focused traffic engineering actions. The TSM alternative generally serves as the baseline against which a proposed transit alternative is compared in the New Starts process.

Travel Time: The elapsed time between a trip’s beginning and end. It includes travel, transfers, and waiting time.

Unlinked Passenger Trips: (also called boardings) The number of times passengers board public transportation vehicles. Passengers are counted each time they board vehicles no matter how many vehicles they use to travel from their origin to their destination and regardless of whether they pay a fare, use a pass or transfer, or ride for free.

Zoning: Designation of the land area within a municipality into discrete zones for the purpose of controlling uses and density (e.g., single-family residential, multi-family residential, commercial, and industrial). The state grants authority to municipalities to regulate land use through zoning.